Senior police officers who have dealt with armed sieges feel the public and media have little understanding of the realities of policing and the dangers faced. The Mark Saunders siege lasted for five hours, with police accused of lacking patience. After a 15-day siege in east London in 2003, they faced accusations of being too patient.

Bob Quick was in overall charge at one the longest sieges in Britain in Hackney, east London, when Eli Hall fired at police before holing up in a flat for more than a fortnight. Police were criticised for not ending the standoff earlier by storming the flat. Quick said: "I felt the pressure from the public and media saying we should go in. It didn't influence me, it was nonsense."

The end came when Hall shot at police, who returned fire and wounded him. Hall then set his flat ablaze and shot himself dead.

Quick, a former assistant commissioner in charge of special operations, said that during an armed siege police priorities are to stop the gunman from harming the public or police.

But the starting point is containment, that is making sure the gunman stays where he is. Quick said: "Any minute he could run into the street and shoot anyone he found, and you have to put containment in to stop the gunman from getting in a position where they can endanger life."

Put simply, police want to avoid a Hungerford-style situation where a gunman roams around an area shooting people.

Quick said: "If you've got someone in that state of mind, who is unstable, angry and has been drinking, who is armed with a weapon, you cannot allow them freedom of movement with that weapon. The public would not forgive the police."

The aim is for a peaceful resolution. Quick said: "There are procedures that are designed to minimise the risk posed to the public and police and where possible, safeguard the rights of the armed individual.

"Police are encouraged to negotiate. The basic model is containment and negotiation."

One senior firearms officer with experience of sieges said the newspaper headlines failed to accurately convey the level of danger faced by the officers dealing with Saunders: "Shotguns make a very big mess, they have a very big spray [of fire]."

Another senior officer put it more succinctly: "If you shoot at the police, you should expect to get shot."

In the 2003 Hackney siege where Quick was in charge, he let the gunman's mother talk to him to try to get him to surrender. It did not work. In the Saunders siege police were criticised for not allowing his wife to talk to him.

The senior firearms officer with experience of armed sieges added: "I would go through lots of tactics before going to the family, because it can backfire. If they have opened fire, are waving a gun around and are drunk, it is possible they may not be too happy in their relationship."

All senior officers spoken to by the Guardian said the Saunders siege was a situation rarely faced by police in this country, where an armed man is holed up, with some of his neighbours trapped, and he has repeatedly opened fire.

Quick said: "The decision to fire is an individual one. Before every deployment a statutory warning is given to armed officer about their powers and duty under the law."

If a gunman points a weapon, Quick said an officer's duty is clear: "They issue an armed challenge, if they can, to get him to surrender. If he made a threatening move they would be entitled to fire upon him, to negate the threat to life."